Wall Chart Atlas (All Charts, 14 Pages)
The complete shop wall-chart atlas in one printable file — matching, markings, strength, threads and selection charts, letter size.
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Text version of this sheet
THE FASTENER APP
PRINTABLE SHOP WALL CHART
Bolt · Nut · Washer Matching Chart
Tape this behind the counter · the print still wins
A574
MFG
307A
A307A
307B
A307B
MFG
MFG
MFG
MFG
A325
A490
MFG
MFG
8.8
MFG
10.9
12.9
316
MFG
MFG
MFG
A574
Grade 2
A307 A
A307 B
Grade 5
Grade 8
A325
A490
8.8
10.9
12.9
316
Bolt / screw specified
Typical nut
Typical washer
Finish / note
J429 Grade 2
J995 Gr 2 or 5 hex
USS or SAE flat
Zinc or plain
A307 Grade A
A563 A / hex nut
USS or SAE flat
CURRENT · 60 ksi · std hex
A307 Grade B
Heavy hex nut as specified
As specified
CURRENT · flange / piping
J429 Grade 5
J995 Grade 5
SAE / USS; hardened if print
Zinc common; HE if plated
J429 Grade 8
J995 Gr 8 or A563 DH
Hardened preferred
Plate only with HE control
F3125 A325
A563 C or DH as specified
ASTM F436
HDG as a matched system
F3125 A490
A563 DH / DH3
ASTM F436
Coating restricted
F1852 / F2280 TC
Matched TC nut only
Matched TC washer
Do not mix kegs
F593 Group 1 (304)
F594 Group 1
Stainless flat
Anti-seize — galling
F593 Group 2 (316)
F594 Group 2
316 washer
Marine default
ISO 8.8
ISO class 8 nut
ISO flat / hardened as spec
Watch coarse vs fine
ISO 10.9 / 12.9
Class 10 / 12 nut
Hardened when specified
HE if plated
A574 socket cap
Tapped hole or high-grade nut
Hardened if used
Not F837 stainless
A193 B7
A194 Grade 2H
Hardened / as specified
High-temp service
A574 / 12.9
A nut that spins on is not automatically the right nut.
Thread fit is the lowest bar. Strength, coating oversize, lubrication and the named specification are the real match.
WALL CHART / TRAINING AID ONLY. Not engineering advice. Verify current SAE, ASTM, ISO, ASME and OEM documents. Pairing lines are typical sho…
WC-01 · letter landscape
THE FASTENER APP
PRINTABLE SHOP WALL CHART
Hold It Up to the Head — Common Markings
Lines and numbers = grade · MFG = manufacturer logo, not the grade
307A
A307A
307B
A307B
MFG
MFG
SAE Grade 2
A307 Grade A
A307 Grade B
SAE Grade 5
SAE Grade 8
F3125 A325
F3125 A490
No radial lines. Plain head +
maker mark. A blank head is
not proof of Grade 2.
CURRENT. 307A stamp. 60
CURRENT. 307B stamp.
ksi carbon. Standard hex.
Looks like Grade 2.
Flange / cast-iron piping.
Often heavy hex.
Three radial lines at 120°.
Medium-strength Q&T.
Everyday machinery.
Six radial lines. High strength.
Cat / Deere / trailer joints
when specified.
Heavy hex stamped A325.
Structural system — not a
Grade 5 cap screw.
Heavy hex stamped A490.
Higher-strength structural
system.
MFG
MFG
MFG
A325
A490
MFG
MFG
A574
A325
8.8
10.9
12.9
316
MFG
MFG
MFG
MFG
MFG
B7
MFG
A574
F1852 TC
Metric 8.8
Metric 10.9
Metric 12.9
316 / F593 G
A574 / 12.9 socket
A193 B7 stud
Round spline / twist-off head.
Matched assembly. Do not
mix kegs.
Stamped 8.8. Common metric
machinery class. Not
automatically Grade 5.
Stamped 10.9. High-strength
metric. Watch plating /
hydrogen.
Stamped 12.9. Highest
common metric class. Often
sockets.
Alloy or F593 condition
stamp. Marine / chloride
default over 304.
Cylindrical head + hex socket.
Black is not a grade. Read
the stamp.
Grade on the stud end + heat
/ maker ID. Pair with A194
2H.
WALL CHART / TRAINING AID ONLY. Not engineering advice. Verify current SAE, ASTM, ISO, ASME and OEM documents. Pairing lines are typical sho…
WC-02 · letter landscape
THE FASTENER APP
PRINTABLE SHOP WALL CHART
Inch Grades vs Metric Classes
Similar tensile numbers are not a free swap · thread, nut, head and spec still have to match
INCH · SAE J429
METRIC · ISO 898-1
Grade 2
MFG
No lines
Tensile neighborhood: 74 ksi ≤3/4
Shop use: Light hardware
Class 8.8
8.8
Tensile neighborhood: 800 MPa
Shop use: Metric machinery
Grade 5
MFG
3 lines
Tensile neighborhood: 120 ksi ≤1 in
Shop use: Machinery / trucks
Class 10.9
10.9
6 lines
10.9 stamp
MFG
Tensile neighborhood: 1040 MPa
Shop use: High-strength metric
Grade 8
MFG
8.8 stamp
MFG
Class 12.9
12.9
12.9 stamp
MFG
Tensile neighborhood: 150 ksi
Shop use: Heavy equipment
Tensile neighborhood: 1220 MPa
Shop use: Sockets / tooling
Do not treat Grade 5 as 8.8, or Grade 8 as 10.9 / 12.9.
Different thread series, head geometry, nut standards and installation rules. If the drawing says one spec, sell that spec.
WALL CHART / TRAINING AID ONLY. Not engineering advice. Verify current SAE, ASTM, ISO, ASME and OEM documents. Pairing lines are typical sho…
WC-03 · letter landscape
THE FASTENER APP
PRINTABLE SHOP WALL CHART
Fastener Wall Chart · Marks + Matching
11 × 17 · print at the copy shop · hang at the counter
MFG
307A
A307A
307B
A307B
MFG
MFG
MFG
MFG
A325
A490
MFG
MFG
Grade 2
A307 A
A307 B
Grade 5
Grade 8
A325
A490
No lines
CURRENT 60 ksi
CURRENT flange
3 lines
6 lines
Heavy hex
Heavy hex
A574
A325
MFG
8.8
10.9
12.9
316
MFG
MFG
MFG
MFG
B7
MFG
A574
A325 TC
8.8
10.9
12.9
316
A574
B7
Spline head
Metric
Metric
Metric
Stainless
Socket
Stud end
Specified fastener
Typical nut
Typical washer
Finish note
Grade 2
J995 2/5
USS/SAE
Zinc/plain
A307 A
A563 A / hex
USS/SAE
CURRENT · std hex
A307 B
Heavy hex nut
As specified
CURRENT · flanges
Grade 5
J995 5
SAE/USS
Zinc; HE if plated
Grade 8
J995 8 / DH
Hardened
HE control
A325
A563 C/DH
F436
System + HDG
A490
A563 DH
F436
Coating restricted
8.8
Class 8 nut
ISO washer
Coarse vs fine
10.9 / 12.9
Class 10/12
Hardened
HE if plated
304 / 316
F594 same group
SS washer
Anti-seize
A574 socket
High-grade nut
Hardened
Not F837
B7
A194 2H
As specified
High temp
Match the part in your hand to the drawing. MFG is the manufacturer — not the grade.
A nut that spins on is not the test. Strength, coating, lubrication and the named specification are the match. The print wins.
WALL CHART / TRAINING AID ONLY. Not engineering advice. Verify current SAE, ASTM, ISO, ASME and OEM documents. Pairing lines are typical sho…
WC-04 · tabloid 11×17 landscape
THE FASTENER APP
COMPLETE WALL ATLAS · 1 of 4 · 11×17
Hold the fastener up to this wall
Lines = SAE grade · Decimal numbers = ISO property class · Letters = ASTM / alloy · MFG = maker, not grade
307A
A307A
307B
A307B
MFG
MFG
SAE Grade 2
A307 Grade A
A307 Grade B
SAE Grade 5
SAE Grade 8
Grade L9
F3125 A325
F3125 A490
F1852 TC
No radial lines
A307A + maker
A307B + maker
3 lines @ 120°
6 lines @ 60°
9 lines @ 40°
Heavy hex A325
Heavy hex A490
Spline / twist-off
Low strength · 74 ksi ≤¾
CURRENT · 60 ksi · std hex
CURRENT · flange / piping
Medium · 120 ksi ≤1 in
High · 150 ksi
Very high · ~180 ksi
Structural 120 ksi
Structural 150 ksi
A325-strength TC kit
A490
4.6
8.8
10.9
12.9
A2-70
A4-70
A4-80
316
MFG
MFG
MFG
MFG
MFG
MFG
MFG
MFG
MFG
MFG
MFG
MFG
MFG
A325
A490
A325
MFG
MFG
MFG
F2280 TC
Class 4.6
Class 8.8
Class 10.9
Class 12.9
A2-70
A4-70
A4-80
F593 / 316
Spline / twist-off
Stamped 4.6
Stamped 8.8
Stamped 10.9
Stamped 12.9
304 family
316 family
316 high strength
Alloy or F593G/H
A490-strength TC kit
400 MPa low carbon
800 / 830 MPa
1040 MPa
1220 MPa · sockets
700 MPa austenitic
700 MPa · marine
800 MPa cold work
Inch stainless
NYLOC
DH
A574
B7
A449
BD
BC
MFG
MFG
MFG
MFG
36
A574
F436
55
105
F1554
A574 SHCS
A193 B7
ASTM A449
A354 BD
A354 BC
Nyloc nut
A563 DH nut
F436 washer
F1554 ends
Black socket ≠ grade
Stamp on stud end
A449 + maker
BD + maker
BC + maker
Nylon ring
DH on face
Hardened
Blue / yellow / red
170–180 ksi alloy
Pair with A194 2H
Grade-5 family, ASTM
Grade-8 family, ASTM
Between Gr 5 and Gr 8
Prevailing torque
Structural / Gr 8 nut
A325 / A490 system
36 / 55 / 105 · replaced A307 C
A blank head is not proof of Grade 2 or A307. A307 A and B are CURRENT. A307 C was withdrawn 2007 — use F1554 Grade 36.
Grade symbol ≠ manufacturer logo. Count lines or read the number. Then open the matching nut / washer / finish line on page 3.
COMPLETE WALL ATLAS — training / identification aid only. Not a substitute for SAE J429, ISO 898, ISO 3506, ASTM F3125/F593/A193/A563/F1554 or OEM data. Values are widely published summaries. Size splits apply. The print wins. MFG is a placeholder manufacturer mark, not a grade.
THE FASTENER APP
COMPLETE WALL ATLAS · 2 of 4 · 11×17
Mechanical properties — published summary values
Confirm diameter splits in the current standard. ksi = 1,000 psi. 1 MPa ≈ 145 psi. 8.8 is not a free swap for Grade 5.
METRIC · ISO 898-1
Mark / spec
Material idea
Size split
Proof
Yield min
Tensile min
Gr 2 (no lines)
Low/med carbon
¼–¾ in
55 ksi
57 ksi
74 ksi
Class
Proof MPa
Yield MPa
Tensile MPa
≈ ksi ten.
225
240
400
58
Gr 2 larger
Same, hot formed
>¾–1½ in
33 ksi
36 ksi
60 ksi
4.6
A307 A
Low carbon
¼–4 in
—
—
60 ksi
4.8
310
340
420
61
A307 B
Flange / piping
¼–4 in
—
—
60–100 ksi
5.8
380
420
520
75
Gr 5 (3 lines)
Med carbon Q&T
¼–1 in
85 ksi
92 ksi
120 ksi
8.8 ≤M16
580
640
800
116
Gr 5 larger
Med carbon Q&T
>1–1½ in
74 ksi
81 ksi
105 ksi
8.8 >M16
600
660
830
120
A449 ~1 in
Q&T carbon/alloy
through ~1 in
85 ksi
92 ksi
120 ksi
9.8
650
720
900
131
A325 Type 1/3
Structural Q&T
½–1 in
85 ksi
92 ksi
120 ksi
10.9
830
940
1040
151
A325 larger
Structural Q&T
1■–1½ in
74 ksi
81 ksi
105 ksi
12.9
970
1100
1220
177
Gr 8 (6 lines)
Med carbon alloy Q&T
¼–1½ in
120 ksi
130 ksi
150 ksi
A354 BC
Alloy Q&T
check diameter
size split
size split
~125 ksi class
A354 BD
Alloy Q&T
check diameter
120 ksi class
130 ksi class
150 ksi class
A490 Type 1/3
Structural alloy
½–1½ in
120 ksi
130 ksi
150 ksi
L9 (9 lines)
Alloy Q&T
common small/med
—
—
~180 ksi
Mark
Family
Tensile idea
A574 SHCS ≤½
Alloy socket
#0–½ in
140 ksi
153 ksi
180 ksi
A2-50
304 family soft
500 MPa
A574 SHCS >½
Alloy socket
>½–4 in
135 ksi
153 ksi
170 ksi
A2-70
304 / 18-8 CW
700 MPa
A193 B7
Cr-Mo high temp
see A193 table
—
105 ksi typ ≤2½
125 ksi typ ≤2½
A4-50
316 family soft
500 MPa
F1554 Gr 36
Anchor · blue end
½–4 in
—
36 ksi
58–80 ksi
A4-70
316 marine default
700 MPa
F1554 Gr 55
Anchor · yellow end
½–4 in
—
55 ksi
75–95 ksi
A4-80
316 high strength
800 MPa
F1554 Gr 105
Anchor · red end
½–3 in typ
—
105 ksi
125–150 ksi
F593C/D
Group 1 304 inch
cond. + size
F593G/H
Group 2 316 inch
cond. + size
410 / C1
Martensitic
not A2/A4
STAINLESS · ISO 3506 / F593
COMMON THREADS · MEASURE BEFORE YOU MATCH
Size
UNC TPI
UNF TPI
Metric
Coarse pitch
Fine pitch
¼ / M6
20
28
M6
1.0
0.75
5/16 / M8
18
24
M8
1.25
1.0
■ / M10
16
24
M10
1.5
1.25
7/16
14
20
M12
1.75
1.5
½ / M12
13
20
M14
2.0
1.5
■ / M16
11
18
M16
2.0
1.5
¾ / M20
10
16
M20
2.5
1.5
■
9
14
M24
3.0
2.0
1 / M24
8
12
M30
3.5
2.0
NEAREST STRENGTH — NOT EQUIVALENTS
• Gr 2 ≈ 4.6 / 4.8 neighborhood. Gr 5 ≈ 8.8. Gr 8 ≈ 10.9. 12.9 has no SAE twin.
• A325 is a structural SYSTEM (head, thread length, nut, washer, method).
• A4-70 at 700 MPa is well below Grade 8 at 150 ksi (~1034 MPa).
• 08.8 (leading zero) is reduced-loadability — not interchangeable with 8.8.
COMPLETE WALL ATLAS — training / identification aid only. Not a substitute for SAE J429, ISO 898, ISO 3506, ASTM F3125/F593/A193/A563/F1554 or OEM data. Values are widely published summaries. Size splits apply. The print wins. MFG is a placeholder manufacturer mark, not a grade.
THE FASTENER APP
COMPLETE WALL ATLAS · 3 of 4 · 11×17
Nuts, washers, matching, coatings, anchors
Nut class must develop the bolt proof load. HDG changes fit. Electroplate + high strength = hydrogen control.
Specified fastener
Typical nut
Typical washer
Finish / process note
SAE Grade 2
J995 Gr 2 or 5
USS or SAE flat
Zinc or plain
A307 Grade A
A563 A / hex nut
USS or SAE flat
CURRENT · standard hex · 60 ksi
A307 Grade B
Heavy hex nut as specified
As specified
CURRENT · flange / cast-iron piping
A307 Grade C
Do not sell as current
—
WITHDRAWN 2007 → F1554 Gr 36
SAE Grade 5
J995 Grade 5
SAE/USS; harden if print
Zinc common · HE if plated
SAE Grade 8
J995 Gr 8 or A563 DH
Hardened preferred
Plate only with bake/HE control
Grade L9
Matched high-strength nut
Hardened
Treat as engineered product
F3125 A325
A563 C or DH as specified
ASTM F436 same type
HDG as a matched system
F3125 A490
A563 DH / DH3
ASTM F436 same type
Usually not HDG / electroplated
F1852 / F2280 TC
Matched TC nut only
Matched TC washer
Do not mix kegs or lots
ISO 8.8
ISO class 8 nut
ISO flat / hardened
Coarse vs fine pitch
ISO 10.9
ISO class 10 nut
Hardened
HE if plated
ISO 12.9
ISO class 12 nut
Hardened HV high
Often socket into tapped hole
F593 Group 1 (304)
F594 Group 1
Stainless flat
Anti-seize — galling
F593 Group 2 (316)
F594 Group 2
316 washer
Marine / chloride default
A2-70 / A4-70
Matching A2 / A4 nut
Stainless
Do not mix A2 nut on A4 bolt
A574 socket cap
Tapped hole or high-grade nut
Hardened if used
Not F837 stainless socket
F837 stainless SHCS
Stainless nut / tapped SS
Stainless
Much weaker than A574
A193 B7
A194 Grade 2H
As specified
High-temperature service
A193 B8 / B8M
A194 8 / 8M
As specified
Stainless high/low temp
F1554 Gr 36 / 55 / 105
Matched nut per spec
As specified
Color code on exposed end
A354 BD
A563 DH class
Hardened
Coating + HE controls
HDG any high-strength
Overtapped nut when required
HDG washer of right spec
Dimensional growth is real
NUT MARKS YOU WILL ACTUALLY SEE
DH
MFG
MFG
J995 Gr 5
J995 Gr 8
8
NYLOC
PT
F594
ISO 8
Nyloc
All-metal PT
F594 SS
MFG
A563 DH
ISO 10
COATINGS · THE WALL-CHART RULES
F1554 ANCHOR COLOR · EXPOSED END
• Zinc electroplate: common, thin, decorative-to-mild corrosion. High-strength parts need hydrogen process control.
• Hot-dip galvanize: thick, outdoor/structural. Grows threads. Needs a galvanize-able grade and often an overtapped nut.
• Mechanical zinc / zinc-flake: used when HDG heat or electroplate hydrogen is the wrong risk.
• A490 / 10.9 / 12.9 / BD: do not send out for bargain plating. Specify finish with the grade.
• Type 3 weathering (A325/A490): extra marking rules. Do not paint over the identity and guess later.
Common shop color code (confirm the project spec):
BLUE end = Grade 36
YELLOW end = Grade 55
RED end = Grade 105
Color is an aid, not a mill cert. Heat number and grade stamp still rule.
Do not cut the colored end off and then argue about the grade.
Match nut to the grade. A Grade 36 nut on a 105 rod is a specification break.
Embedment, projection, galvanizing and weldability are project decisions.
COMPLETE WALL ATLAS — training / identification aid only. Not a substitute for SAE J429, ISO 898, ISO 3506, ASTM F3125/F593/A193/A563/F1554 or OEM data. Values are widely published summaries. Size splits apply. The print wins. MFG is a placeholder manufacturer mark, not a grade.
THE FASTENER APP
COMPLETE WALL ATLAS · 4 of 4 · 11×17
Product forms, torque, lockers, shop laws
Geometry identifies many of these — they do not carry SAE grade lines. Read the part, then the spec.
A574
10.9
MFG
A574
Hex cap / hex bolt
Socket head cap
Button socket
Flat socket
Machine screw
Self-drilling
Cap screw usually fully or longer threaded; bolt often partial. Spec still
rules.
A574 inch or 12.9 metric. F837 if stainless.
Lower head. Different load path than SHCS.
Countersunk. Head sits in the hole.
Often unmarked. Material is the spec.
Drill point + washer head. Not a grade-8 bolt.
NYLOC
MFG
END ID
Thread-forming
Lag screw
Carriage bolt
Threaded rod
Lock washer
Nylon locknut
Point and thread form ID the part.
Wood / timber. Many commodity lags unmarked.
Round dome + square neck.
End stamp / color / tag. Appearance ≠ spec.
Split / tooth geometry. Not a substitute for preload.
Reuse limits. Temperature limits the insert.
TORQUE · T = K × D × F
THREADLOCKER COLORS
SHOP LAWS
• F is usually ~75% of proof load — a model, not a law.
• Purple 222 — low, small screws
• The drawing beats the chart.
• Blue 242/243 — medium, serviceable
• Do not swap Gr 5 ↔ 8.8 or Gr 8 ↔ 10.9.
• K ≈ 0.20 dry · 0.18 zinc · 0.15 waxed. Finish moves the number more than grade does.
• Charts assume as-received threads, a specific K, and no prevailing-torque nut.
• Nyloc, distorted-thread nuts, anti-seize and HDG all invalidate a generic chart.
• Red 262/271 — high, heat to remove
• Structural joints use RCSC / turn-of-nut / TC spline — not a Grade 8 dry chart.
• When the OEM publishes a torque, that number wins.
• Green 290 — wicking, preassembled
• A307 A/B are current. A307 C is not.
• Do not swap A325 ↔ Grade 5 cap screw.
• Do not mix TC kegs.
• Primer on stainless, zinc, inactive metals
• Color is a vendor convention — read the bottle
• Not a substitute for proper preload
• Do not upgrade strength to 'be safe.'
• Do not downgrade because the nut fits.
• UNC and UNF are different parts.
• Metric coarse and fine are different parts.
• If it is structural, pressure, lifting or safety — demand the cert.
COMPLETE WALL ATLAS — training / identification aid only. Not a substitute for SAE J429, ISO 898, ISO 3506, ASTM F3125/F593/A193/A563/F1554 or OEM data. Values are widely published summaries. Size splits apply. The print wins. MFG is a placeholder manufacturer mark, not a grade.
THE FASTENER APP
WC-06 · large print
Inch hex wrench sizes
ASME B18.2.1 standard hex · ASME B18.2.6 / F3125 heavy hex · A307 Grade A uses STANDARD hex
Nominal size
Common threads
Standard hex wrench
Heavy hex wrench
Used on
1/4 in
20 UNC / 28 UNF
7/16 in
—
Gr 2 / 5 / 8 / A307 A
5/16 in
18 UNC / 24 UNF
1/2 in
—
Gr 2 / 5 / 8 / A307 A
3/8 in
16 UNC / 24 UNF
9/16 in
11/16 in *
Standard vs heavy hex
7/16 in
14 UNC / 20 UNF
5/8 in
—
Gr 2 / 5 / 8 / A307 A
1/2 in
13 UNC / 20 UNF
3/4 in
7/8 in
A325 / A490 take 7/8
9/16 in
12 UNC / 18 UNF
13/16 in
15/16 in
Standard vs heavy
5/8 in
11 UNC / 18 UNF
15/16 in
1-1/16 in
A325 / A490 take 1-1/16
3/4 in
10 UNC / 16 UNF
1-1/8 in
1-1/4 in
A325 / A490 take 1-1/4
7/8 in
9 UNC / 14 UNF
1-5/16 in
1-7/16 in
A325 / A490 take 1-7/16
1 in
8 UNC / 12 UNF
1-1/2 in
1-5/8 in
A325 / A490 take 1-5/8
1-1/8 in
7 UNC / 12 UNF
1-11/16 in
1-13/16 in
Structural heavy hex
1-1/4 in
7 UNC / 12 UNF
1-7/8 in
2 in
Structural heavy hex
1-1/2 in
6 UNC / 12 UNF
2-1/4 in
2-3/8 in
Structural heavy hex
A 1/4-20 HEX CAP SCREW TAKES A 7/16 WRENCH — NOT A 1/4 WRENCH
1/4 is the thread diameter. The head flats are 7/16. Same rule at every size.
A307 Grade A = standard hex (this left column). A307 Grade B flange bolts are often HEAVY hex.
A325 / A490 are always heavy hex. A 1/2 A325 will not accept a 3/4 socket. * Structural F3125 starts at 1/2.
LARGE-PRINT DIMENSIONAL AID. ASME B18.2.1 / B18.2.6 / B18.2.2 / B18.3 and ISO 4014/4017 / 4032 / 4762. A307 Grades A and B are current. A307 Grade C was withdrawn 2007 — use F1554 Grade 36. Confirm current year of standard.
THE FASTENER APP
WC-07 · large print
Inch Allen / hex-key sizes
ASME B18.3 · socket head cap screws use a LARGER key than button or flat of the same diameter
Screw size
SHCS Allen key
Button-head key
Flat-head key
SHCS head diameter
#4
3/32 in
1/16 in
1/16 in
0.183 in
#6
7/64 in
5/64 in
5/64 in
0.226 in
#8
9/64 in
3/32 in
3/32 in
0.270 in
#10
5/32 in
1/8 in
1/8 in
0.312 in
1/4 in
3/16 in
5/32 in
5/32 in
0.375 in
5/16 in
1/4 in
3/16 in
3/16 in
0.469 in
3/8 in
5/16 in
7/32 in
7/32 in
0.562 in
7/16 in
3/8 in
1/4 in
1/4 in
0.656 in
1/2 in
3/8 in
5/16 in
5/16 in
0.750 in
5/8 in
1/2 in
3/8 in
3/8 in
0.938 in
3/4 in
5/8 in
1/2 in
1/2 in
1.125 in
7/8 in
3/4 in
—
—
1.312 in
1 in
3/4 in
—
—
1.500 in
1/4 SOCKET CAP = 3/16 ALLEN
1/4 BUTTON OR FLAT = 5/32 ALLEN
Do not grab the SHCS key for a button or flat of the same thread.
7/16 and 1/2 SHCS share a 3/8 key. Rounding that socket ruins two sizes.
Black oxide is not a grade. Inch alloy sockets are usually A574. Stainless sockets are F837.
LARGE-PRINT DIMENSIONAL AID. ASME B18.2.1 / B18.2.6 / B18.2.2 / B18.3 and ISO 4014/4017 / 4032 / 4762. A307 Grades A and B are current. A307 Grade C was withdrawn 2007 — use F1554 Grade 36. Confirm current year of standard.
THE FASTENER APP
WC-08 · large print
Metric hex wrench sizes
ISO 4014 / 4017 hex bolts and ISO 4032 nuts · DIN 934 nuts differ at M10 and M12
Size
Coarse pitch
ISO hex / ISO nut
DIN 934 nut (shop)
What to grab first
M5
0.8 mm
8 mm
8 mm
8 mm socket
M6
1.0 mm
10 mm
10 mm
10 mm socket
M8
1.25 mm
13 mm
13 mm
13 mm socket
M10
1.5 mm
16 mm
17 mm
Try 16 first, then 17
M12
1.75 mm
18 mm
19 mm
Try 18 first, then 19
M14
2.0 mm
21 mm
22 mm
Try 21 first, then 22
M16
2.0 mm
24 mm
24 mm
24 mm socket
M18
2.5 mm
27 mm
27 mm
27 mm socket
M20
2.5 mm
30 mm
30 mm
30 mm socket
M22
2.5 mm
32 mm
32 mm
32 mm socket
M24
3.0 mm
36 mm
36 mm
36 mm socket
M30
3.5 mm
46 mm
46 mm
46 mm socket
M36
4.0 mm
55 mm
55 mm
55 mm socket
THE M10 / M12 TRAP
ISO M10 hex and ISO 4032 nut = 16 mm. Many DIN 934 M10 nuts = 17 mm.
ISO M12 = 18 mm. Many DIN 934 M12 nuts = 19 mm. Same idea at M14 (21 vs 22).
If the 16 mm socket will not start on an M10 nut, you likely have a DIN nut — not a wrong bolt.
LARGE-PRINT DIMENSIONAL AID. ASME B18.2.1 / B18.2.6 / B18.2.2 / B18.3 and ISO 4014/4017 / 4032 / 4762. A307 Grades A and B are current. A307 Grade C was withdrawn 2007 — use F1554 Grade 36. Confirm current year of standard.
THE FASTENER APP
WC-09 · large print
Metric Allen / hex-key sizes
ISO 4762 / DIN 912 socket caps · button ISO 7380 and flat ISO 10642 use a SMALLER key
Size
SHCS key (4762)
Button key
Flat key
SHCS head / height
M3
2.5 mm
2.0 mm
2.0 mm
5.5 mm / 3 mm
M4
3 mm
2.5 mm
2.5 mm
7 mm / 4 mm
M5
4 mm
3 mm
3 mm
8.5 mm / 5 mm
M6
5 mm
4 mm
4 mm
10 mm / 6 mm
M8
6 mm
5 mm
5 mm
13 mm / 8 mm
M10
8 mm
6 mm
6 mm
16 mm / 10 mm
M12
10 mm
8 mm
8 mm
18 mm / 12 mm
M14
12 mm
—
—
21 mm / 14 mm
M16
14 mm
10 mm
10 mm
24 mm / 16 mm
M20
17 mm
12 mm
12 mm
30 mm / 20 mm
M24
19 mm
—
—
36 mm / 24 mm
M30
22 mm
—
—
45 mm / 30 mm
M6 SOCKET CAP TAKES A 5 mm KEY — NOT A 6 mm KEY
ISO 4762 head height equals the thread size: an M8 cap head is 8 mm tall.
Button and flat keys step down one size. Low-head sockets (DIN 7984) also use a smaller key.
Metric sockets are often 12.9. Stainless metric sockets are ISO 3506 — not the same strength.
LARGE-PRINT DIMENSIONAL AID. ASME B18.2.1 / B18.2.6 / B18.2.2 / B18.3 and ISO 4014/4017 / 4032 / 4762. A307 Grades A and B are current. A307 Grade C was withdrawn 2007 — use F1554 Grade 36. Confirm current year of standard.
THE FASTENER APP
WC-10 · large print
ASTM A307 is still valid
Grade A and Grade B are current · Grade C was withdrawn in 2007 and replaced by F1554 Grade 36
307A
A307A
307B
A307B
MFG
MFG
MFG
36
55
105
F1554
A307 Grade A
A307 Grade B
Looks like Grade 2
F1554 replaced Gr C
Grade
Status today
Typical product
Tensile idea
Wrench family
A307 Grade A
CURRENT
General hex bolts, studs, rod
60 ksi min
STANDARD hex
A307 Grade B
CURRENT
Flange / cast-iron piping
60-100 ksi
Often HEAVY hex
A307 Grade C
WITHDRAWN 2007
Old anchor-bolt grade
Was 58-80 ksi
Use F1554 Gr 36
F1554 Grade 36
CURRENT replacement
Anchor rods / headed anchors
58-80 ksi, 36 yield
Blue end common
DO NOT TREAT A307 AS A325, AND DO NOT TREAT A BLANK HEAD AS A307
A307 Grade A is low-strength carbon steel in the Grade 2 neighborhood. It is not structural F3125.
Many A307 A heads carry only a manufacturer mark. A blank head is not proof of A307 — demand the cert.
If the drawing says A307 C or 'A307 anchor,' the current spec is F1554 Grade 36 unless the engineer still calls C.
A36 is a plate/shape steel spec. A307 is the fastener spec. Specify A307 when you want a bolt.
LARGE-PRINT DIMENSIONAL AID. ASME B18.2.1 / B18.2.6 / B18.2.2 / B18.3 and ISO 4014/4017 / 4032 / 4762. A307 Grades A and B are current. A307 Grade C was withdrawn 2007 — use F1554 Grade 36. Confirm current year of standard.
THE FASTENER APP
WC-11 · large print
The sizes you grab every day
Read this from three feet away · thread diameter is not the tool size
If you are holding
You need this tool
1/4-20 hex cap / A307 Grade A
7/16 in wrench or socket
1/4-20 socket cap (Allen)
3/16 in hex key
5/16 hex cap
1/2 in wrench
3/8 hex cap
9/16 in wrench
1/2 hex cap (Grade 5 / 8)
3/4 in wrench
1/2 A325 / A490 heavy hex
7/8 in wrench
5/8 hex cap
15/16 in wrench
5/8 A325 / A490
1-1/16 in wrench
3/4 hex cap
1-1/8 in wrench
3/4 A325 / A490
1-1/4 in wrench
M6 hex / M6 SHCS
10 mm wrench / 5 mm key
M8 hex / M8 SHCS
13 mm wrench / 6 mm key
M10 ISO hex / DIN nut
16 mm first, then 17 mm
M12 ISO hex / DIN nut
18 mm first, then 19 mm
M12 SHCS
10 mm hex key
A307 GRADE A USES THE STANDARD HEX WRENCH — SAME TOOL AS GRADE 2 / 5 / 8 OF THAT DIAMETER
Heavy hex is a different tool. If the 3/4 socket will not fit a 1/2 bolt, you are holding a structural / heavy-hex head.
LARGE-PRINT DIMENSIONAL AID. ASME B18.2.1 / B18.2.6 / B18.2.2 / B18.3 and ISO 4014/4017 / 4032 / 4762. A307 Grades A and B are current. A307 Grade C was withdrawn 2007 — use F1554 Grade 36. Confirm current year of standard.
Fastener Guide reference FG-3EA6A1 · thefastenerapp.com/fastener-guide/wall-charts/wall-chart-atlas · © The Fastener App. Reference only — verify the current governing standard, drawing and manufacturer data before specifying or installing.
